Fluidic circuits for sample preparation including bio-discs and methods relating thereto

Abstract

A fluidic circuit for receiving a fluid and separating a component of a fluid from the fluid comprises a separation chamber for receiving the fluid, an air chamber in fluid communication with the separation chamber, and a return channel in fluid communication with the separation chamber. In an advantageous embodiment, the fluidic circuit is subjected to a force, such as a centrifugal force, so that substantially all of the component of the fluid is moved to the return channel while substantially all remaining portions of the fluid are moved to the separation chamber.

1 . An optical disc for processing and analyzing a sample, comprising:
 a substantially circular substrate;   a cap portion;   a channel layer positioned between said substrate and said cap portion, said channel layer comprising at least one fluidic circuit, said fluidic circuit comprising:   a mixing chamber configured to mix said sample with a fluid, said mixing chamber having a first end and a second end and defining a serpentine configuration;   a valve connected to said first end of said mixing chamber;   a separation chamber having a port, the separation chamber configured to receive said sample and to separate a portion of said sample when the optical disc is rotated;   a sample circuit configured to pass said portion of said sample to said mixing chamber, said sample circuit comprising a sample flow channel with a first and second end, said first end connected to said port and positioned closer to the center of said optical disc than said second end and configured to introduce a volume of said portion of said sample from said separation chamber into said sample flow channel, and said second end in fluid communication with said valve, wherein said valve is configured to prevent interaction of said portion of said sample with said fluid, and to prevent flow of said portion of said sample out of said sample flow channel through said second end and said valve and into said mixing chamber until the optical disc is rotated at a predetermined speed which causes said portion of said sample to be forced through said valve;   a fluid circuit configured to pass said fluid to said mixing chamber, said fluid circuit comprising a fluid flow channel with a first and second end, said first end positioned closer to the center of said optical disc than said second end and configured to introduce a volume of said fluid into said fluid flow channel, and said second end in fluid communication with said valve, wherein said valve is configured to prevent interaction of said portion of said sample with said fluid, and to prevent flow of said volume of said fluid out of said fluid flow channel through said second end and said valve and into said mixing chamber until the optical disc is rotated at said predetermined speed;   
     
     
         2 . The optical disc of  claim 1 , wherein interior surfaces of said mixing chamber comprise one or more corners defining interior chamber angles of between 5 and 160 degrees. 
     
     
         3 . The optical disc of  claim 2 , wherein said one or more corners are at about 90 degrees. 
     
     
         4 . The optical disc of  claim 1  wherein said valve comprises a capillary valve.